FREQUENT - Frequent values

You are given a sequence of n integers a1 , a2 , ... , an in non-decreasing order. In addition to that, you are given several queries consisting of indices i and j (1 ≤ i ≤ j ≤ n). For each query, determine the most frequent value among the integers ai , ... , aj.

Input Specification

The input consists of several test cases. Each test case starts with a line containing two integers n and q (1 ≤ n, q ≤ 100000). The next line contains n integers a1 , ... , an (-100000 ≤ ai ≤ 100000, for each i ∈ {1, ..., n}) separated by spaces. You can assume that for each i ∈ {1, ..., n-1}: ai ≤ ai+1. The following q lines contain one query each, consisting of two integers i and j (1 ≤ i ≤ j ≤ n), which indicate the boundary indices for the query.

The last test case is followed by a line containing a single 0.

Output Specification

For each query, print one line with one integer: The number of occurrences of the most frequent value within the given range.

Sample Input

10 3
-1 -1 1 1 1 1 3 10 10 10
2 3
1 10
5 10
0

Sample Output

1
4
3

A naive algorithm may not run in time!

Added by:Adrian Kuegel
Date:2007-07-06
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:University of Ulm Local Contest 2007

hide comments
2015-04-28 21:48:55 Sunil
bridges, mse06h , niceday are all very similar problems
2015-04-20 12:55:56 GAURAV CHANDEL
Very good segment tree problem....
2015-01-04 12:31:55 aditi
Please give some more testcases..Getting WA
2014-12-23 10:04:25 tyler_durden
what should you do in case of a tie .?
2014-11-17 00:33:58 Archangel
how to break ties? for example if the input array is
5 10 10 10 and the query is for the interval 2 to 3 then what will be the answer as both 5 and 10 are having same frequencies
2014-11-07 15:53:56 Maulik Soneji
Got many WAs and TLEs but finally did it.
Don't use cin cout or else it will be TLE
2014-10-25 19:42:13 harrypotter192
Don't miss the "many test cases" part
2014-08-31 23:42:26 Z
a1,a2,..,an can be negative,be careful!
2014-08-29 18:41:51 yaswanth
See that array is sorted ;)
© Spoj.com. All Rights Reserved. Spoj uses Sphere Engine™ © by Sphere Research Labs.